Syngamus trachea

Also known as:

Red Louse Cattle Chewing Louse

• The 'gapeworm' - an atypical strongyloid.
• Deep red in colour.
• 'Y'-shaped as the smaller male is permanently attached to the female.
• Lives in the trachea.
• Wide host range, including many wild birds (rooks and crows commonly affected) as well as poultry and game birds.
• Causes respiratory distress (gapes), especially in young birds.

Life-Cycle

• The egg is like a typical strongyle egg, except that there is an operculum at each end.
• Infective larva develops inside the egg.
• Birds can be infected by ingesting:
  • the larvated egg
  • the larva after hatching out of the egg
  • or by eating an earthworm (transport host) that has previously swallowed an egg or larva.

Epidemiology

Gapes is a common and serious problem in pheasant poults. A common sequence of events is as follows:

• Infected wild birds (e.g. crows):

→ droppings on ground

→ soil contaminated with Syngamus eggs

→ earthworms infected

→ reservoir of infection

→ eaten by pheasant poults reared on earth-floored pens in woodland

→ disease.